tests: shell: better parameters for the interval stack overflow test

Wider testing has shown that 128 kB stack is too low (e.g. for systems
with 64 kB page size), leading to false failures in some environments.

Based on results from a matrix of RHEL 8 and RHEL 9 systems across
x86_64, aarch64, ppc64le and s390x architectures as well as some
anecdotal testing of other Linux distros on x86_64 machines, 400 kB
seems safe: the normal nft stack (which should stay constant during
this test) on all tested systems doesn't exceed 200 kB (stays around
100 kB on typical systems with 4 kB page size), while always growing
beyond 500 kB in the failing case (nftables before baecd1cf2685) with
the increased set size.

Fixes: d8ccad2a2b73 ("tests: cover baecd1cf2685 ("segtree: Fix segfault when restoring a huge interval set")")
Signed-off-by: Štěpán Němec <snemec@redhat.com>
Signed-off-by: Phil Sutter <phil@nwl.cc>

diff --git a/tests/shell/testcases/sets/0068interval_stack_overflow_0 b/tests/shell/testcases/sets/0068interval_stack_overflow_0
index 6620572449c3ca3d920bb3fce86f6c3055cfa780..2cbc986802644a96e5a51eabeb328099421d3195 100755 (executable)
--- a/tests/shell/testcases/sets/0068interval_stack_overflow_0
+++ b/tests/shell/testcases/sets/0068interval_stack_overflow_0
@@ -9,7 +9,7 @@ trap 'rm -f "$ruleset_file"' EXIT
 {
        echo 'define big_set = {'
        for ((i = 1; i < 255; i++)); do
-               for ((j = 1; j < 80; j++)); do
+               for ((j = 1; j < 255; j++)); do
                        echo "10.0.$i.$j,"
                done
        done
@@ -26,4 +26,4 @@ table inet test68_table {
 }
 EOF
 
-( ulimit -s 128 && $NFT -f "$ruleset_file" )
+( ulimit -s 400 && $NFT -f "$ruleset_file" )